Fragrances are an important part of cosmetic compositions since their primary role is to create an agreeable sensory experience for their consumer, in addition to providing malodor coverage or other more functional roles.
Perfumes are composed of odorants with a wide range of chemical properties including molecular weights, vapor pressures and diffusivities as well as different polarities and chemical functionalities. Using these different properties, one can create different hedonic profiles describing the fragrance.
Fragrance materials are generally small molecular weight substances with a vapor pressure that allows their molecules to evaporate, become airborne, and eventually reach the olfactory organ of a living entity.
There are a variety of different fragrance materials with different functional groups and molecular weights, both of which affect their vapor pressures and hence the ease with which they can be sensed.
Odorants used in perfumery offer a wide array of polarity ranging from the somewhat water miscible to the water immiscible chemical compounds. Perfumery in the various wash-off applications spanning from cosmetic to industrial and household have different functionalities and must be engineered to fulfill certain needs and objectives. Perfumes' effect and quality during use plays a big role in the consumer's purchase intent as well and the desire of the consumer to purchase the product again.
Prior art pertaining to perfumery for water based rinse-off applications deals largely with general physical properties of odorants such as boiling point and clogP values. U.S. Pat. No. 6,143,707 discloses automatic dishwashing detergent with what is defined as blooming fragrance compositions by the authors. These perfumes contain so-called “blooming perfume ingredients,” and optional “delayed blooming” ingredients as well as “non-blooming ingredients.” “Blooming” odorants were chosen based on their clogP and boiling point values. The logP value of an odorant is defined as the ratio between its equilibrium concentration in octanol and in water. The logP value of many of the fragrance materials have been reported and are available in databases such as the Pomona92 database, the Daylight Chemical Information Systems, Inc, Irvine, Calif. The logP can also be very conveniently calculated using the fragment approach of Hansch and Leo. See A. Leo, Comprehensive Medicinal Chemistry, Vol. 4, C. Hansch et al. p 295, Pergamon press, 1990. These logP values are referred to as clogP values. Odorants thought to result in bloom in water dilutions are thought to have clogP of at least 3.0 and boiling points of less than 260° C.
The same rationale for dishwashing liquids with blooming perfumes was also filed in U.S. Patent Application No. 2004/0138078. EP Patent No. 0888440B1 relates to a glass cleaning composition containing “blooming perfumes” based on criteria mentioned above. U.S. Pat. No. 6,601,789 discloses toilet bowl cleaning compositions also containing “blooming perfumes” made of odorants chosen based on their clogP values of at least 3.0 and boiling points of less that 260° C. Odorants with delayed bloom are thought to have a clogP of less than 3.0 and boiling point values less than 250° C.